Retention of gallium ions from acidic solutions by pyridine strong‐base anion exchangers

Using the batch method, the retention of Ga(III) from HCl solutions by two gel‐type pyridine strong‐base anion exchangers containing 1‐methyl‐ or 1‐butyl‐4‐vinylpyridinium chloride structural units, called S₁ and S₂ resins, respectively, was studied. The influence of the HCl and Ga(III) concentrations as well as of the contact time between the resin and the liquid phase was investigated. The parameters, which characterize the retention process, were estimated using Langmuir and Freundlich isotherms. Both resins exhibited a higher affinity for gallium ions from a 6M HCl solution. According to Langmuir isotherms, maximum retention capacities of 44.44 and 60 mg Ga(III)/g dry resin for the S₁ and S₂ resins, respectively, were obtained. Freundlich isotherms provide additional proof for a higher affinity of the S₂ resin for Ga(III) from HCl solutions. It is clear that the substituent length increase on N⁺ atoms led to an increasing affinity of the pyridine strong base anion exchangers toward Ga(III). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3440–3444, 2002     

炉壁集束碳氧枪在电炉中的应用

介绍了鄂钢电炉厂70t consteel 电炉使用炉壁集束碳氧枪后对经济指标的改善,以及在生产实践中的冶金效果.     

过渡金属碳化物的催化研究进展

过渡金属碳化物作为一种催化新材料得到了人们广泛的关注,在催化加氢、脱氢、脱硫(HDS)、脱氮(HDN)和重整等方面,表现出优良的催化活性和选择性.综述了碳化钒、碳化钼、碳化钨、碳化铁、碳化钛等碳化物的催化性能和碳化物在各个反应中的催化机理的研究进展.     

Chemistry and Physics of Alkali Metals on MoS2 Surfaces

The interaction of alkali metal with surfaces has been of great interest to the community of catalysis since alkali metal can play an important role as a promoter. On alkali-doped MoS₂, such a promotion effect of alkali metal has been exemplified in the direct synthesis of linear alcohols from CO and H₂, where the alkali-doping switches the catalyst selectivity from methanation to alcohol synthesis. This paper reviews recent high-resolution X-ray photoelectron spectroscopy experiments that have provided direct observation of electron transfer from alkali metals to a model single crystal MoS₂ and the capture of the supra-valence electrons in the subsequent oxidation reactions.     

A detailed analysis of ambipolar diffusion in nanostructured metal oxide films

In this paper a transport equation is derived which describes the behaviour of the nanostructured metal oxide films in a photoelectrochemical cell. It is shown that a detailed analysis of the charge compensation mechanism necessarily leads to a transport equation with characteristics similar to but logically distinct from the pure diffusion equation. The studied phenomenon was named ambipolar diffusion in the early 1950s. It takes into account the fact that the diffusion processes of ions and electrons occur at different speeds. A weak electric field therefore couples the processes together to preserve charge neutrality. The electric field in turn affects the transport resulting in a deviation from purely diffusive behaviour. However, this has not been widely recognised in the literature for nanostructured semiconductor films until very recently. In this paper a detailed analysis is presented. It is based on the assumption that the current density is solenoidal. It is shown that application of the ambipolar diffusion model to a photoelectrochemical cell based on a nanostructured metal oxide film leads to an additional term in the transport equation, rather than only a new diffusion coefficient as in earlier work. It is also shown that the boundary conditions interact closely with the equation to form a transport model.     

左江水利枢纽厂房及闸坝金属结构设计简介

简介左江水利枢纽水电站厂房及闸坝金属结构系统的组成、布置及结构设计。其金属结构设备有各种门(栅)44道,各种闸门、拦污栅28扇,各种启闭机18台套,设备总重2100t。工程建成后,运行情况良好。     

固载于SBA-15分子筛中的同双核金属配合物催化剂

合成了3种同双核金属配合物[M2LCl3]Cl(L代表配体三亚乙基四胺,M代表Co,Cu,Cr),采用微波加热法合成了SBA-15分子筛,采用浸渍法将3种同双核金属配合物分别固载在表面官能化的SBA-15分子筛(SBA-15-NH2分子筛)中制得负载型催化剂。傅里叶变换红外光谱、X射线衍射、紫外可见光谱和热分析表征结果表明,同双核金属配合物被固载后,其结构仍保持完整。以环己烷氧化反应为探针反应,考察了[Co2LCl3]Cl/SBA-15-NH2,[Cu2LCl3]Cl/SBA-15-NH2,[Cr2LCl3]Cl/SBA-15-NH2催化剂的活性,环己烷转化率分别为11.0%,49.5%,57.9%;对于[Cr2LCl3]Cl/SBA-15-NH2催化剂,当分别以乙睛、丙酮和冰醋酸为溶剂时,环己烷转化率分别为57.9%,52.1%,34.2%,3次重复实验的环己烷转化率分别为57.9%,47.8%,46.5%,表明该催化剂具有较好的活性和重复使用性。     

地下水污染修复的活性渗滤墙技术

活性渗滤墙是一种现场修复受污染地下水的新型技术，具有原理简单，施工方便，运行费用低廉等特点，活性渗滤墙垂直于地下水流动方向设置，当地下水流通过活性渗滤墙时，污染物与墙体材料发生化学反应，从而达到环境修复的目的。文中综述了活性渗滤墙技术的修复机理和实际应用，大量研究表明，应用金属铁作为活性渗滤墙材料，可以去除地下水中的重金属以及有机污染物，目前活性渗滤墙已经在世界各地应用，是一种非常有发展前景的环境污染修复技术。     

新型处理药剂（EP-110）处理各种重金属离子的实验研究

各行各业生产过程中会产生大量废水,重金属离子污染物是其中的重要控制指标,传统的处理方法不能完全解 决这类污染。本文通过大量的实验数据,对新型的处理药剂(EP-110)处理各种重金属离子的性能做了全面的测试、分析,并 提出了使用方法。